<?php
/**
 * Zend Framework
 *
 * LICENSE
 *
 * This source file is subject to the new BSD license that is bundled
 * with this package in the file LICENSE.txt.
 * It is also available through the world-wide-web at this URL:
 * http://framework.zend.com/license/new-bsd
 * If you did not receive a copy of the license and are unable to
 * obtain it through the world-wide-web, please send an email
 * to license@zend.com so we can send you a copy immediately.
 *
 * @category   Zend
 * @package    Zend_Db
 * @subpackage Adapter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 * @version    $Id: Oracle.php 19048 2009-11-19 18:15:05Z mikaelkael $
 */

/**
 * @see Zend_Db_Adapter_Abstract
 */
require_once 'Zend/Db/Adapter/Abstract.php';

/**
 * @see Zend_Db_Statement_Oracle
 */
require_once 'Zend/Db/Statement/Oracle.php';

/**
 * @category   Zend
 * @package    Zend_Db
 * @subpackage Adapter
 * @copyright  Copyright (c) 2005-2009 Zend Technologies USA Inc. (http://www.zend.com)
 * @license    http://framework.zend.com/license/new-bsd     New BSD License
 */
class Zend_Db_Adapter_Oracle extends Zend_Db_Adapter_Abstract
{
	/**
	 * User-provided configuration.
	 *
	 * Basic keys are:
	 *
	 * username => (string) Connect to the database as this username.
	 * password => (string) Password associated with the username.
	 * dbname   => Either the name of the local Oracle instance, or the
	 *             name of the entry in tnsnames.ora to which you want to connect.
	 * persistent => (boolean) Set TRUE to use a persistent connection
	 * @var array
	 */
	protected $_config = array(
        'dbname'       => null,
        'username'     => null,
        'password'     => null,
        'persistent'   => false
	);

	/**
	 * Keys are UPPERCASE SQL datatypes or the constants
	 * Zend_Db::INT_TYPE, Zend_Db::BIGINT_TYPE, or Zend_Db::FLOAT_TYPE.
	 *
	 * Values are:
	 * 0 = 32-bit integer
	 * 1 = 64-bit integer
	 * 2 = float or decimal
	 *
	 * @var array Associative array of datatypes to values 0, 1, or 2.
	 */
	protected $_numericDataTypes = array(
	Zend_Db::INT_TYPE    => Zend_Db::INT_TYPE,
	Zend_Db::BIGINT_TYPE => Zend_Db::BIGINT_TYPE,
	Zend_Db::FLOAT_TYPE  => Zend_Db::FLOAT_TYPE,
        'BINARY_DOUBLE'      => Zend_Db::FLOAT_TYPE,
        'BINARY_FLOAT'       => Zend_Db::FLOAT_TYPE,
        'NUMBER'             => Zend_Db::FLOAT_TYPE,
	);

	/**
	 * @var integer
	 */
	protected $_execute_mode = null;

	/**
	 * Default class name for a DB statement.
	 *
	 * @var string
	 */
	protected $_defaultStmtClass = 'Zend_Db_Statement_Oracle';

	/**
	 * Check if LOB field are returned as string
	 * instead of OCI-Lob object
	 *
	 * @var boolean
	 */
	protected $_lobAsString = null;

	/**
	 * Creates a connection resource.
	 *
	 * @return void
	 * @throws Zend_Db_Adapter_Oracle_Exception
	 */
	protected function _connect()
	{
		if (is_resource($this->_connection)) {
			// connection already exists
			return;
		}

		if (!extension_loaded('oci8')) {
			/**
			 * @see Zend_Db_Adapter_Oracle_Exception
			 */
			require_once 'Zend/Db/Adapter/Oracle/Exception.php';
			throw new Zend_Db_Adapter_Oracle_Exception('The OCI8 extension is required for this adapter but the extension is not loaded');
		}

		$this->_setExecuteMode(OCI_COMMIT_ON_SUCCESS);

		$connectionFuncName = ($this->_config['persistent'] == true) ? 'oci_pconnect' : 'oci_connect';

		$this->_connection = @$connectionFuncName(
		$this->_config['username'],
		$this->_config['password'],
		$this->_config['dbname'],
		$this->_config['charset']);

		// check the connection
		if (!$this->_connection) {
			/**
			 * @see Zend_Db_Adapter_Oracle_Exception
			 */
			require_once 'Zend/Db/Adapter/Oracle/Exception.php';
			throw new Zend_Db_Adapter_Oracle_Exception(oci_error());
		}
	}

	/**
	 * Test if a connection is active
	 *
	 * @return boolean
	 */
	public function isConnected()
	{
		return ((bool) (is_resource($this->_connection)
		&& get_resource_type($this->_connection) == 'oci8 connection'));
	}

	/**
	 * Force the connection to close.
	 *
	 * @return void
	 */
	public function closeConnection()
	{
		if ($this->isConnected()) {
			oci_close($this->_connection);
		}
		$this->_connection = null;
	}

	/**
	 * Activate/deactivate return of LOB as string
	 *
	 * @param string $lob_as_string
	 * @return Zend_Db_Adapter_Oracle
	 */
	public function setLobAsString($lobAsString)
	{
		$this->_lobAsString = (bool) $lobAsString;
		return $this;
	}

	/**
	 * Return whether or not LOB are returned as string
	 *
	 * @return boolean
	 */
	public function getLobAsString()
	{
		if ($this->_lobAsString === null) {
			// if never set by user, we use driver option if it exists otherwise false
			if (isset($this->_config['driver_options']) &&
			isset($this->_config['driver_options']['lob_as_string'])) {
				$this->_lobAsString = (bool) $this->_config['driver_options']['lob_as_string'];
			} else {
				$this->_lobAsString = false;
			}
		}
		return $this->_lobAsString;
	}

	/**
	 * Returns an SQL statement for preparation.
	 *
	 * @param string $sql The SQL statement with placeholders.
	 * @return Zend_Db_Statement_Oracle
	 */
	public function prepare($sql)
	{
		$this->_connect();
		$stmtClass = $this->_defaultStmtClass;
		if (!class_exists($stmtClass)) {
			require_once 'Zend/Loader.php';
			Zend_Loader::loadClass($stmtClass);
		}
		$stmt = new $stmtClass($this, $sql);
		if ($stmt instanceof Zend_Db_Statement_Oracle) {
			$stmt->setLobAsString($this->getLobAsString());
		}
		$stmt->setFetchMode($this->_fetchMode);
		return $stmt;
	}

	/**
	 * Quote a raw string.
	 *
	 * @param string $value     Raw string
	 * @return string           Quoted string
	 */
	protected function _quote($value)
	{
		if (is_int($value) || is_float($value)) {
			return $value;
		}
		$value = str_replace("'", "''", $value);
		return "'" . addcslashes($value, "\000\n\r\\\032") . "'";
	}

	/**
	 * Quote a table identifier and alias.
	 *
	 * @param string|array|Zend_Db_Expr $ident The identifier or expression.
	 * @param string $alias An alias for the table.
	 * @param boolean $auto If true, heed the AUTO_QUOTE_IDENTIFIERS config option.
	 * @return string The quoted identifier and alias.
	 */
	public function quoteTableAs($ident, $alias = null, $auto = false)
	{
		// Oracle doesn't allow the 'AS' keyword between the table identifier/expression and alias.
		return $this->_quoteIdentifierAs($ident, $alias, $auto, ' ');
	}

	/**
	 * Return the most recent value from the specified sequence in the database.
	 * This is supported only on RDBMS brands that support sequences
	 * (e.g. Oracle, PostgreSQL, DB2).  Other RDBMS brands return null.
	 *
	 * @param string $sequenceName
	 * @return string
	 */
	public function lastSequenceId($sequenceName)
	{
		$this->_connect();
		$sql = 'SELECT '.$this->quoteIdentifier($sequenceName, true).'.CURRVAL FROM dual';
		$value = $this->fetchOne($sql);
		return $value;
	}

	/**
	 * Generate a new value from the specified sequence in the database, and return it.
	 * This is supported only on RDBMS brands that support sequences
	 * (e.g. Oracle, PostgreSQL, DB2).  Other RDBMS brands return null.
	 *
	 * @param string $sequenceName
	 * @return string
	 */
	public function nextSequenceId($sequenceName)
	{
		$this->_connect();
		$sql = 'SELECT '.$this->quoteIdentifier($sequenceName, true).'.NEXTVAL FROM dual';
		$value = $this->fetchOne($sql);
		return $value;
	}

	/**
	 * Gets the last ID generated automatically by an IDENTITY/AUTOINCREMENT column.
	 *
	 * As a convention, on RDBMS brands that support sequences
	 * (e.g. Oracle, PostgreSQL, DB2), this method forms the name of a sequence
	 * from the arguments and returns the last id generated by that sequence.
	 * On RDBMS brands that support IDENTITY/AUTOINCREMENT columns, this method
	 * returns the last value generated for such a column, and the table name
	 * argument is disregarded.
	 *
	 * Oracle does not support IDENTITY columns, so if the sequence is not
	 * specified, this method returns null.
	 *
	 * @param string $tableName   OPTIONAL Name of table.
	 * @param string $primaryKey  OPTIONAL Name of primary key column.
	 * @return string
	 */
	public function lastInsertId($tableName = null, $primaryKey = null)
	{
		if ($tableName !== null) {
			$sequenceName = $tableName;
			if ($primaryKey) {
				$sequenceName .= "_$primaryKey";
			}
			$sequenceName .= '_seq';
			return $this->lastSequenceId($sequenceName);
		}

		// No support for IDENTITY columns; return null
		return null;
	}

	/**
	 * Returns a list of the tables in the database.
	 *
	 * @return array
	 */
	public function listTables()
	{
		$this->_connect();
		$data = $this->fetchCol('SELECT table_name FROM all_tables');
		return $data;
	}

	/**
	 * Returns the column descriptions for a table.
	 *
	 * The return value is an associative array keyed by the column name,
	 * as returned by the RDBMS.
	 *
	 * The value of each array element is an associative array
	 * with the following keys:
	 *
	 * SCHEMA_NAME      => string; name of schema
	 * TABLE_NAME       => string;
	 * COLUMN_NAME      => string; column name
	 * COLUMN_POSITION  => number; ordinal position of column in table
	 * DATA_TYPE        => string; SQL datatype name of column
	 * DEFAULT          => string; default expression of column, null if none
	 * NULLABLE         => boolean; true if column can have nulls
	 * LENGTH           => number; length of CHAR/VARCHAR
	 * SCALE            => number; scale of NUMERIC/DECIMAL
	 * PRECISION        => number; precision of NUMERIC/DECIMAL
	 * UNSIGNED         => boolean; unsigned property of an integer type
	 * PRIMARY          => boolean; true if column is part of the primary key
	 * PRIMARY_POSITION => integer; position of column in primary key
	 * IDENTITY         => integer; true if column is auto-generated with unique values
	 *
	 * @todo Discover integer unsigned property.
	 *
	 * @param string $tableName
	 * @param string $schemaName OPTIONAL
	 * @return array
	 */
	public function describeTable($tableName, $schemaName = null)
	{
		$version = $this->getServerVersion();
		if (($version === null) || version_compare($version, '9.0.0', '>=')) {
			$sql = "SELECT TC.TABLE_NAME, TC.OWNER, TC.COLUMN_NAME, TC.DATA_TYPE,
                    TC.DATA_DEFAULT, TC.NULLABLE, TC.COLUMN_ID, TC.DATA_LENGTH,
                    TC.DATA_SCALE, TC.DATA_PRECISION, C.CONSTRAINT_TYPE, CC.POSITION
                FROM ALL_TAB_COLUMNS TC
                LEFT JOIN (ALL_CONS_COLUMNS CC JOIN ALL_CONSTRAINTS C
                    ON (CC.CONSTRAINT_NAME = C.CONSTRAINT_NAME AND CC.TABLE_NAME = C.TABLE_NAME AND CC.OWNER = C.OWNER AND C.CONSTRAINT_TYPE = 'P'))
                  ON TC.TABLE_NAME = CC.TABLE_NAME AND TC.COLUMN_NAME = CC.COLUMN_NAME
                WHERE UPPER(TC.TABLE_NAME) = UPPER(:TBNAME)";
			$bind[':TBNAME'] = $tableName;
			if ($schemaName) {
				$sql .= ' AND UPPER(TC.OWNER) = UPPER(:SCNAME)';
				$bind[':SCNAME'] = $schemaName;
			}
			$sql .= ' ORDER BY TC.COLUMN_ID';
		} else {
			$subSql="SELECT AC.OWNER, AC.TABLE_NAME, ACC.COLUMN_NAME, AC.CONSTRAINT_TYPE, ACC.POSITION
                from ALL_CONSTRAINTS AC, ALL_CONS_COLUMNS ACC
                  WHERE ACC.CONSTRAINT_NAME = AC.CONSTRAINT_NAME
                    AND ACC.TABLE_NAME = AC.TABLE_NAME
                    AND ACC.OWNER = AC.OWNER
                    AND AC.CONSTRAINT_TYPE = 'P'
                    AND UPPER(AC.TABLE_NAME) = UPPER(:TBNAME)";
			$bind[':TBNAME'] = $tableName;
			if ($schemaName) {
				$subSql .= ' AND UPPER(ACC.OWNER) = UPPER(:SCNAME)';
				$bind[':SCNAME'] = $schemaName;
			}
			$sql="SELECT TC.TABLE_NAME, TC.OWNER, TC.COLUMN_NAME, TC.DATA_TYPE,
                    TC.DATA_DEFAULT, TC.NULLABLE, TC.COLUMN_ID, TC.DATA_LENGTH,
                    TC.DATA_SCALE, TC.DATA_PRECISION, CC.CONSTRAINT_TYPE, CC.POSITION
                FROM ALL_TAB_COLUMNS TC, ($subSql) CC
                WHERE UPPER(TC.TABLE_NAME) = UPPER(:TBNAME)
                  AND TC.OWNER = CC.OWNER(+) AND TC.TABLE_NAME = CC.TABLE_NAME(+) AND TC.COLUMN_NAME = CC.COLUMN_NAME(+)";
			if ($schemaName) {
				$sql .= ' AND UPPER(TC.OWNER) = UPPER(:SCNAME)';
			}
			$sql .= ' ORDER BY TC.COLUMN_ID';
		}

		$stmt = $this->query($sql, $bind);

		/**
		 * Use FETCH_NUM so we are not dependent on the CASE attribute of the PDO connection
		 */
		$result = $stmt->fetchAll(Zend_Db::FETCH_NUM);

		$table_name      = 0;
		$owner           = 1;
		$column_name     = 2;
		$data_type       = 3;
		$data_default    = 4;
		$nullable        = 5;
		$column_id       = 6;
		$data_length     = 7;
		$data_scale      = 8;
		$data_precision  = 9;
		$constraint_type = 10;
		$position        = 11;

		$desc = array();
		foreach ($result as $key => $row) {
			list ($primary, $primaryPosition, $identity) = array(false, null, false);
			if ($row[$constraint_type] == 'P') {
				$primary = true;
				$primaryPosition = $row[$position];
				/**
				 * Oracle does not support auto-increment keys.
				 */
				$identity = false;
			}
			$desc[$this->foldCase($row[$column_name])] = array(
                'SCHEMA_NAME'      => $this->foldCase($row[$owner]),
                'TABLE_NAME'       => $this->foldCase($row[$table_name]),
                'COLUMN_NAME'      => $this->foldCase($row[$column_name]),
                'COLUMN_POSITION'  => $row[$column_id],
                'DATA_TYPE'        => $row[$data_type],
                'DEFAULT'          => $row[$data_default],
                'NULLABLE'         => (bool) ($row[$nullable] == 'Y'),
                'LENGTH'           => $row[$data_length],
                'SCALE'            => $row[$data_scale],
                'PRECISION'        => $row[$data_precision],
                'UNSIGNED'         => null, // @todo
                'PRIMARY'          => $primary,
                'PRIMARY_POSITION' => $primaryPosition,
                'IDENTITY'         => $identity
			);
		}
		return $desc;
	}

	/**
	 * Leave autocommit mode and begin a transaction.
	 *
	 * @return void
	 */
	protected function _beginTransaction()
	{
		$this->_setExecuteMode(OCI_DEFAULT);
	}

	/**
	 * Commit a transaction and return to autocommit mode.
	 *
	 * @return void
	 * @throws Zend_Db_Adapter_Oracle_Exception
	 */
	protected function _commit()
	{
		if (!oci_commit($this->_connection)) {
			/**
			 * @see Zend_Db_Adapter_Oracle_Exception
			 */
			require_once 'Zend/Db/Adapter/Oracle/Exception.php';
			throw new Zend_Db_Adapter_Oracle_Exception(oci_error($this->_connection));
		}
		$this->_setExecuteMode(OCI_COMMIT_ON_SUCCESS);
	}

	/**
	 * Roll back a transaction and return to autocommit mode.
	 *
	 * @return void
	 * @throws Zend_Db_Adapter_Oracle_Exception
	 */
	protected function _rollBack()
	{
		if (!oci_rollback($this->_connection)) {
			/**
			 * @see Zend_Db_Adapter_Oracle_Exception
			 */
			require_once 'Zend/Db/Adapter/Oracle/Exception.php';
			throw new Zend_Db_Adapter_Oracle_Exception(oci_error($this->_connection));
		}
		$this->_setExecuteMode(OCI_COMMIT_ON_SUCCESS);
	}

	/**
	 * Set the fetch mode.
	 *
	 * @todo Support FETCH_CLASS and FETCH_INTO.
	 *
	 * @param integer $mode A fetch mode.
	 * @return void
	 * @throws Zend_Db_Adapter_Oracle_Exception
	 */
	public function setFetchMode($mode)
	{
		switch ($mode) {
			case Zend_Db::FETCH_NUM:   // seq array
			case Zend_Db::FETCH_ASSOC: // assoc array
			case Zend_Db::FETCH_BOTH:  // seq+assoc array
			case Zend_Db::FETCH_OBJ:   // object
				$this->_fetchMode = $mode;
				break;
			case Zend_Db::FETCH_BOUND: // bound to PHP variable
				/**
				* @see Zend_Db_Adapter_Oracle_Exception
				*/
				require_once 'Zend/Db/Adapter/Oracle/Exception.php';
				throw new Zend_Db_Adapter_Oracle_Exception('FETCH_BOUND is not supported yet');
				break;
			default:
				/**
				 * @see Zend_Db_Adapter_Oracle_Exception
				 */
				require_once 'Zend/Db/Adapter/Oracle/Exception.php';
				throw new Zend_Db_Adapter_Oracle_Exception("Invalid fetch mode '$mode' specified");
				break;
		}
	}

	/**
	 * Adds an adapter-specific LIMIT clause to the SELECT statement.
	 *
	 * @param string $sql
	 * @param integer $count
	 * @param integer $offset OPTIONAL
	 * @return string
	 * @throws Zend_Db_Adapter_Oracle_Exception
	 */
	public function limit($sql, $count, $offset = 0)
	{
		$count = intval($count);
		if ($count <= 0) {
			/**
			 * @see Zend_Db_Adapter_Oracle_Exception
			 */
			require_once 'Zend/Db/Adapter/Oracle/Exception.php';
			throw new Zend_Db_Adapter_Oracle_Exception("LIMIT argument count=$count is not valid");
		}

		$offset = intval($offset);
		if ($offset < 0) {
			/**
			 * @see Zend_Db_Adapter_Oracle_Exception
			 */
			require_once 'Zend/Db/Adapter/Oracle/Exception.php';
			throw new Zend_Db_Adapter_Oracle_Exception("LIMIT argument offset=$offset is not valid");
		}

		/**
		 * Oracle does not implement the LIMIT clause as some RDBMS do.
		 * We have to simulate it with subqueries and ROWNUM.
		 * Unfortunately because we use the column wildcard "*",
		 * this puts an extra column into the query result set.
		 */
		$limit_sql = "SELECT z2.*
            FROM (
                SELECT z1.*, ROWNUM AS \"zend_db_rownum\"
                FROM (
                    " . $sql . "
                ) z1
            ) z2
            WHERE z2.\"zend_db_rownum\" BETWEEN " . ($offset+1) . " AND " . ($offset+$count);
		return $limit_sql;
	}

	/**
	 * @param integer $mode
	 * @throws Zend_Db_Adapter_Oracle_Exception
	 */
	private function _setExecuteMode($mode)
	{
		switch($mode) {
			case OCI_COMMIT_ON_SUCCESS:
			case OCI_DEFAULT:
			case OCI_DESCRIBE_ONLY:
				$this->_execute_mode = $mode;
				break;
			default:
				/**
				 * @see Zend_Db_Adapter_Oracle_Exception
				 */
				require_once 'Zend/Db/Adapter/Oracle/Exception.php';
				throw new Zend_Db_Adapter_Oracle_Exception("Invalid execution mode '$mode' specified");
				break;
		}
	}

	/**
	 * @return int
	 */
	public function _getExecuteMode()
	{
		return $this->_execute_mode;
	}

	/**
	 * Inserts a table row with specified data.
	 *
	 * Oracle does not support anonymous ('?') binds.
	 *
	 * @param mixed $table The table to insert data into.
	 * @param array $bind Column-value pairs.
	 * @return int The number of affected rows.
	 */
	public function insert($table, array $bind)
	{
		$i = 0;
		// extract and quote col names from the array keys
		$cols = array();
		$vals = array();
		foreach ($bind as $col => $val) {
			$cols[] = $this->quoteIdentifier($col, true);
			if ($val instanceof Zend_Db_Expr) {
				$vals[] = $val->__toString();
				unset($bind[$col]);
			} else {
				$vals[] = ':'.$col.$i;
				unset($bind[$col]);
				$bind[':'.$col.$i] = $val;
			}
			$i++;
		}

		// build the statement
		$sql = "INSERT INTO "
		. $this->quoteIdentifier($table, true)
		. ' (' . implode(', ', $cols) . ') '
		. 'VALUES (' . implode(', ', $vals) . ')';

		// execute the statement and return the number of affected rows
		$stmt = $this->query($sql, $bind);
		$result = $stmt->rowCount();
		return $result;
	}

	/**
	 * Check if the adapter supports real SQL parameters.
	 *
	 * @param string $type 'positional' or 'named'
	 * @return bool
	 */
	public function supportsParameters($type)
	{
		switch ($type) {
			case 'named':
				return true;
			case 'positional':
			default:
				return false;
		}
	}

	/**
	 * Retrieve server version in PHP style
	 *
	 * @return string
	 */
	public function getServerVersion()
	{
		$this->_connect();
		$version = oci_server_version($this->_connection);
		if ($version !== false) {
			$matches = null;
			if (preg_match('/((?:[0-9]{1,2}\.){1,3}[0-9]{1,2})/', $version, $matches)) {
				return $matches[1];
			} else {
				return null;
			}
		} else {
			return null;
		}
	}
}
